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Fair Value Measurements - Nonrecurring Basis (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 USD ($) engine | Dec. 31, 2017 USD ($) engine aircraft | Dec. 31, 2016 USD ($)
Assets at fair value and gains (losses) recorded |  |  |
Equipment held for sale | $ 789 | $ 34,172 |
Assets at fair value | 1,700 | 1,100 |
Asset write-down | $ 10,651 | $ 24,930 | $ 9,514
Engine Parts |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Number of engines | engine | 7 | 9 |
Aircrafts |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Number of aircraft | aircraft |  | 5 |
Asset write-down |  | $ 4,700 |
Nonrecurring |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Equipment held for lease | $ 17,756 | 23,255 |
Equipment held for sale | 472 | 39,261 |
Assets at fair value | 18,228 | 62,516 |
Total losses on equipment held for lease | (8,893) | (12,879) |
Total losses on equipment held for sale | (1,758) | (12,051) |
Total losses on assets | (10,651) | (24,930) |
Inventory Write-down | 1,800 |  |
Nonrecurring | Engine Parts |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Asset write-down | 8,900 | 16,900 |
Nonrecurring | Level 2 |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Equipment held for lease | 17,756 | 23,255 |
Equipment held for sale | 472 | 39,261 |
Assets at fair value | $ 18,228 | $ 62,516 |
Engines and Related Equipment |  |  |
Assets at fair value and gains (losses) recorded |  |  |
Number of engines | engine | 34 |  |

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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- Definition Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
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